The PSP has a built-in copy of the Flash player, but it's Flash 7, which is too old for the vast majority of Flash content these days. If whatever you want to run doesn't work with Flash 7, you're SOL I'm afraid.

I'm looking to play a flash game, Swords and Sandals. (http://www.flashgore.com/games/29/swords-and-sandals-2-full-version.html) It only needs a mouse, no keyboard input. Is the PSP Flash Player safe on a 3000?